Coal-hoisting apparatus.



No. 882,867. PATENTED MAR. 2A, 1908.

' J. CAMPBELL.

coAL HOISTING APPARATUS.

APPLICATION FILED FEB. 13. 1907.

a SHEETS-SHEET 1.

WITHEISEEIE H 46 42M 4 No. 882,867. PATENTED MAR. 24. 1908.

J. CAMPBELL.

GOAL HOISTING APPARATUS.

APPLICATION FILED 1'3]. 13. 1907.

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PATENTED MAR. 24, 19025.

J. CAMPBELL.

'GOAL HOISTING APPARATUS.

APPLICATION FILED FEB. 13. 1907.

3 SHEETS-SHEET 3.

PATENT @FFIQR JEREMIAH UAJMIPBELL, O1? PROVIDENCE, ILHOIJE ISLAND.

GQAL-HGISTING ".EIA'fllU'S,

Specification or Letters Patent.

li 'aoented. March 2342, 1%08.

Application flied February 1907. fieriaiiho. 357,127

To all whom it may concern:

he known that l, JEREMIAH CAMPBELL, "'irience, in the county of if evidence rate of Rhoclc ishnul citizen of the Titites, l'ia've invented new and. ernent in Coalailoisting Appara- Ah the following a specification. iention relates especially to an im resins for operating the jaws of the log the operating rope "the housings to the sheave cally kept in. position to rope to reeve th ough 11 wi f ment with their edges. This is on because of the great flier which she rope operates in lift :ne load. which strain would (.itherwise 331 both the rope and the housing ii "oweal to rub -inst each other.

relates also to an improved stop member cushion o rename the made -the grali t the tr l eyor oth'linture with which i wl'ien has not position.

i he understood by rsien s in which-- elevation. of a grab, tr on: o ti position. when L' g I; 4 l3 3 a plan of "I e onin ineol'ianisni. Fig. is a vertical 1 .shion, showing its attacln 5 is asection taken 2, the grab being open. a J81 ical section of one of the houso taken on line 6-6 of Fig. 7, and Fig. 7 is section of the housing taken in a plane at right angles to the plane of Fig. 6

A is the boom which is supported from a tower or other support the usual way; Upon this boom runs the" trolley B carrying the usual sheaves b, If over one of which runs the hoisting rope c and over the other of which runs the operating rope d, these two ropes hoistin? operating the grab. One end of each or these ropes is attached to the trolley as at c, d. T he trolley is provided .With the usual. wheels 6 which run on tl e boom A.

F is a yielding stop or cushion shown as depending from the trolley B and adapted to he engaged by some portion of the grab mechanism as it rises, such for example, as the sheave housing 0. The details of these parts are shown in Figs. 3 and a. The structure is sheave-honsinf f} striking the uni lor surface ol; this cylinder oioses it against the plunger, thus iorining an air cushion which. re-.

licves the impact or jar rich would otherwise be caused by the ei'igagenient between he grab and the trolley. When. the grab is lowered again the air leaks by the plunger and the 0 index falls off from the plunger by its own weight into the position shown in Fig. or a s r' mg may he used to it if k by two pairs of arms 6, e, from a having a nut on each end and which the axis of the hoisting sheave C. jaws are also provided with pairs of each of'which carries a huh a through which. passes shaft or pin a having a nut on each end. by which the shaft is l'TOPiZ in pl: e within the hubs of these arms. non 1.0 pin 18 an idler sheave G and housing ii. The L carry a pin on wine sheave ii" the upper ends of the arms 6 per ends of the arms iv a pin on which runs the operating 0D. Each she. is prov deil'with its housing. .The igierating rope d runs from the trolley at d as above described (lOWFi around under the sheave l) and. the sheave l) and up again over the sheave b on the troiley to the hoisting engine, bearing nerhaps on top of the idler sheave G. his Whole construction is such that under ordi nary CODKlilZiOlli-E, as shown in Fig. l, the g ab is hoisted. by means of the rope c w. ich

the grab are kept closed by means of the constant tension upon the operating rope d which holds the sheaVesD, .l) together as shown in Fig, 1. When, however, the oper ating rope (Z is released. the grab opens owing to the weight which it carries and the sheaves l), l) and their supporting arms 6 e ali fall down around the shaft a so that the par s take the position shown in Fig. 5.

When. this operation takes place it Will be noted that considerable slack must be given to the operating rope d and this slack as it '1 runs the operating nasses under the sheave C and the jaws of lies between the sheaves D, D bears upon the middle sheave G which up to this time has been a pure idler.

. similar in al res acts and weighted u on that portion whici hangs upon and be ow the shaft 6 in order that the housing may uniformly remain in this position. The housing is open at its periphery through approximately 270 of its circumference in order to furnish free access to the groove for the operating rope d, its lower portion being closed in to assist in weighting it.

The housings for the sheaves D, D are similar in general character to that just described in that they are weighted so that the may always maintain a fixed relation to he horizontal irrespective of their position on the axis of the sheaves D, D, respectively, with relation to the arms 2', e As be noted from Figs. 6 and 7, the housing in this case comprises two disks (1 bolted together through segments or a rim 05 d. The portions d 02 which'are left open between the segments form passages for the rope d to reeve through as the relations of the sheaves change with relation to the idler G. (Z is a Wei ht which is attached to'the lower portion 0 the housing of each of these sheaves D, D to keep the housingalways-in proper relation to the other parts as above desoribed so that the operating rope (1 Where ,it'passes into and out of the housin will always do so without engagement with any portion of the housing, whether the parts are in the position shown in Fig. 1 or in Fig. 5. To insure the proper weighting of the housing in addition I prefer to provide openings such as (Z to reduce the weight oi the upper portion of the apparatus.

The housing C is similar in character to the other housings, sufficient openings between the two portions being allowed 101 the ropec to adjust itself as circumstances may require. Idlers C, C pivoted between the pairs of arms e, e and e 6, hold the rope when slaokened from falling out of the groove in the sheave C It will be seen from this description when taken in connection with Figs. 5, 6 and 7, that the arms 6', e by which the jaws are operated or allowed to operate, act like scissors. When the grab is to be opened the operating rope d will be released; the sheaves D, D will fall one on each side of the shaft e "being impelled thereto by the weight which the grab holds and as they "fall the parts will take the position shown in Fig. 5, their housings maintaining their relation with the'hori'zontal, but the arms e a taking Ma nearly parallelosition, the operating rope restingupon'the s eave G.

Other means for weightin the 'housin s may be easily 'devised'whic will embo y above described embodiment is simple because it enablesthe ab "to be dismantled without undue troubled Variations in the construction of the cushioning device will also-occur to anyone skilled in the art, the most obvious variation being th reversal of'the parts, placing the yielding member upon the grab and the fixed member upon the trolley,=a'n(l another variation, usefu' when the brought up'not against a trol ey'but a ainst a particular portion of the boom,'is to ocate point.

What I claim as my invention'is 1. A'hoisting apparatus of the'charao'te'r specified comprising a'grab having'swingin'g jaws, crossed arms secured to saidjaws, a pivotal support at the intersection of said arms, sheaves carried by said arms beyond the point of intersection thereof, which which said jaws may be operated, and a sheave mounted upon the dpivotal support of said intersecting arms an 006 rating with the sheaves carried thereby, sii stanti ally as described.

2. A hoisting apparatus 'of the character specified comprising a grab having swinging jaws, a pair of arms secured to each of sai' aws and arranged whereby the pairs of arms may cross one another, a pivotal support for said crossed arms, a sheave carried by each'pair of arms upon the'outer'ends thereof, said sheave being adapted to receive a rope by which said jaws may be operated, and a sheave mounted upon the pivotal support of said arms with which the sheaves carried by said arms are adapted to cooperate whereby the rope operating the jaws of the grab may be maintained in a proper opera tive position with respect to said sheaves.

3. A hoisting apparatus of the character: specified comprising a grab having swinging jaws, crossed arms secured to said jaws, a pivotal support for said intersecting arms, so idler sheave mounted upon said pivotal support, sheaves carried by said arms and adapted to receive a rope for operatingsaid jaws, said sheaves being located on said and cooperate therewith during the operation of said arms, whereby the operating rope may be maintained in a constant operative position by said idler sheave, and means for over-weighting said sheaves to the invention above, referred to, but the.

grab is always one of the members upon the boom atth'at sheaves are adapted to receive a rope by arms to be carried around said idler sheavev having a hoisting pairs of crossed arms pivotally connected together,-,eaeh of said pairs of arms being con- 'nected to one of the jaws of said grab at one end and can'yin an operating sheave at its outer end, anfli ler sheave mounted onthe pivot of said arms, said idler sheave so coop:

} eratingwith said sheaves that an operating rope asfsing round said operating sheaves may e ap roximately in contact with the upperiperip cry of said idler sheave when said ropev istaut, and may rest upon a larger portionibf the" periphery thereof when said rope sis imes, said s eaves being rovided with "weighted housings adapted to e maintained always in the same position with relation to the horizontal, as described.

i5. In a coal hoisting apparatus, a grab having hoisting means comprising a hoisting sheave and hoisting rope surrounding said sheave, and operating means comprising one or more operating sheaves and an operatin rope, each OLSflJCl sheaves being provided with housingsweighted to maintaln them lways in substantially the same vertical posimeans and operating 5 means, said operat ng means comprlsingtwo V 6. In a grab mechanism, a sheave having a housing weighted'to maintain it in a vertical o'sition.

7 n a coal hoisting apparatus, a yielding stop for the grab comprlsing a chambered member and a plunger having a 'sliding fit therein whereby upon the im act of the grab air may be compressed within said cham- Ibered member and gradually expelled therefrom thereby providing a yielding stop to the grab.

8. In a coal hoisting apparatus, a yielding sto for the grab comprising a hollow plunger,

a c ambered member into Which sald plunger is adapted to fit and slide therein, a rod attached to said chambered member and extending through the end of said lunger, and means located and movable wit 'n said plunger for securing theend of said rod.

9. In a coal hoisting ap aratus, a yielding stop having a plunger and cylinder fitted to said plunger, means for allowin the air to pass from the chamber Within the cylinder to the atmosphere, means for guiding the movement of said cylinderwith relation to said plunger,-as set forth. V I JEREMIAH CAMPBELL.

Witnesses:

HENRY C. CRAM, I JAMES A. G ORGE] 

